Messages

61

General Radio Discussion / Re: Hacker Disables More Than 100 Cars Remotely

« on: March 19, 2010, 0033 UTC »

I believe that the buyers knew that the devices were installed - or at least signed the paperwork that said they were aware of it, whether they read it or not.  they apparently install them as part of the deal that let people with lousy credit buy cars on a financing plan.  "Let us install this device that lowers our risk and we'll loan you the money to buy a car; otherwise, you're out of luck."

62

HF Beacons / Re: Can you hear this beacon, 10.133 MHz?

« on: March 04, 2010, 2029 UTC »

On a somewhat related note, however: the "Michigan Mighty Mite" transmitter design - as shown for the 3.5425 and 10.133 MHz beacons - is the basis of the SC Dasher PHFer beacon.  The only changes required are the crystal and number of turns on the coil.  Some guesswork got the first test unit transmitting into a dummy load, and subsequent work with the supplied turns-vs-frequency tables yielded a set of more accurate charts.  It's a simple little transmitter, but it apparently gets out.

63

HF Beacons / Re: 5185 strong

« on: February 09, 2010, 1506 UTC »

Yeah, the lack of standardization - or at least the lack of adherence to said standards - is apparently a big issue in solar cells and panels.

A while back, I picked up some "5 Watt" panels from Harbor Freight, for what amounted to 50% off (big coupon, on top of an existing discount).  One of those sitting inside the workroom window (with double panes, a window screen, and some minor filtering) will float the gel cells on the test beacon, apparently indefinitely.  I had it running for around 3 weeks solid into a dummy load, at a slightly higher duty cycle, and they stayed right up there near the full-charge voltage the entire time.  In an open-air mounting situation, one should be able to float a beacon plus a PIC- or AVR-based keyer without any problems, probably even with a few bells and whistles added on.

64

HF Beacons / Re: 5185 strong

« on: February 08, 2010, 0403 UTC »

Thanks for the report. 

It's been up continuously for almost a week and a half now on the same charge, with no solar panel connected.  I just measured at the terminals, and it's still got 11.6 volts left in the tank, on a pair of 6 volt, 4.5Ah gel cells in series.  The keying is handled by the CMOS version of a 555 chip, using a 2N2222 to switch power to a "Michigan Mighty Mite" transmitter that's been tweaked for operation on the crystal's frequency.  Current drain in a continuous key-down state is right around 125 mA, so it's just sipping at the supply with something like a 25% duty cycle every two seconds.

I got some new tools recently, and I'm looking forward to playing around a bit in the next few days, probably tossing together another test unit or two, to play around with some keying and other experiments.  I'll also be able to look at experimenting with enclosure and mounting options, in hopes of getting this one out "into the wild" before too long.

65

HF Beacons / Re: 2/2 beacon rpt

« on: February 03, 2010, 0422 UTC »

I've always had a solid carrier in the vicinity of CO, and a number of the others.  There are a couple of them where the carrier is close enough that I don't hold out much hope of ever seeing them, but I keep trying. 

Haven't been able to check on any beacons lately, since my main listening antenna has been <ahem> busy.

66

HF Beacons / Re: East Coast Phfer 5185

« on: January 31, 2010, 1432 UTC »

Been trying since announced

Peace!

I would be seriously surprised if you were able to hear this one in western Canada - the original antenna was an east-west shortened dipole, but with questionable performance.  The longwire it's on now is my usual SWL antenna, but due to the way it's strung through the trees, it has strong north-south tendencies.  All of the beacons I hear on it are coming off of a side lobe at best, and it's rare for me to get anything from the western edge of the continent.  Even listening to the hams with "big gun" amplifiers, it's a good day if I hear anything from west of the rocky mountains on this wire.  Squirting 200 mW of RF into it probably isn't going to make the trip over the Divide very well.

I do appreciate your keeping an ear out for it though - hopefully we'll get a day of weird propagation and it'll take a good bounce out that way.  When it warms up a bit, I plan to work on the wire a bit to see if I can't skew the pattern a bit more to an east-west orientation.  When I'm done tinkering with this beacon and it's ready for placement, I plan to give it a westward-pointing antenna, so maybe it'll be easier to pull out of the noise.

Thanks again - still tweaking on it, but happy with it so far...

67

HF Beacons / Re: East Coast Phfer 5185

« on: January 29, 2010, 2128 UTC »

5.185 was off the air for a few hours, but it's back now with a topped-off battery and transmitting around 200 mW into a different antenna.  The shortened dipole it was using before has always been a bit fishy, even on the frequencies it is supposedly tuned for.  Hopefully, it will get a better signal out using the wire.  It's still just a temporary setup, as things are still being tweaked and adjusted.

68

HF Beacons / Re: Blinky

« on: January 25, 2010, 1514 UTC »

Blinky's making it up here, even through the fairly high noise floor this morning.

69

HF Beacons / Re: PROJECT PEANUT launched today at 1800Utc

« on: January 25, 2010, 1513 UTC »

Much better, now.   
With the new battery, Peanut is having no problems making the trip out this way, even punching through local RFI and atmospherics today.

70

HF Beacons / Re: PROJECT PEANUT launched today at 1800Utc

« on: January 24, 2010, 1522 UTC »

Still there, hanging on by its nutty little fingertips!



Just barely on the edge of being audible over the noise floor, but it's there.

Audio:  http://www.rthtg.net/beacons/peanut_24-jan-2010_15-10.wav

Judging by the signal falloff over the last few days, I wouldn't be very surprised at all if this was the last time I were to hear Peanut until it gets a new infusion of juice.

71

HF Beacons / Re: PROJECT PEANUT launched today at 1800Utc

« on: January 20, 2010, 1611 UTC »

Peanut's still there, but fading.

Tuned in to hear it barely making the trip with a noticeable chirp and much weaker signal than before - don't know how much longer the batteries will be able to push a signal out this far.



It's still there in the audio file, but a lot weaker: [link]

Didn't see any photos from the site.

72

HF Beacons / Re: PROJECT PEANUT launched today at 1800Utc

« on: January 17, 2010, 1457 UTC »

Okay, been out of it for a little bit, but...

Peanut was doing pretty well this morning - beautiful, clean-keyed signal into upstate South Carolina this morning as the ionosphere rearranged itself for daytime operations.



Some fading, so the signal went from a beautiful "armchair copy" signal down to virtually nothing and back again over time, but when our little "nutty buddy" was in, it was IN!

Audio file: [link]

Right now (14:55 UTC) it seems to have settled a bit in between the two extremes, with a good, readable signal, clean keying, no chirp, and only moderate fade.

73

HF Beacons / Re: 20 meter dasher testing

« on: January 05, 2010, 1945 UTC »

I've got Peanut, fading in and out, but definitely there on the "ups":



I set the memory slot the other day when I posted my previous image of Peanut's signal - everything is exactly the same: 14.401.000 MHz on the dial, CW mode, no RIT, etc. but now it's sitting right at 2000 Hertz, where the tone was around 750 Hz the other day.  Other than the frequency shift, it's got good, solid keying, no discernible chirp, and no visible drift.

Retuning the radio for exactly 14.400.000 MHz puts the tone at around 980 Hz.
Tuning to center the tone at 750 Hz (where I usually listen to CW, and where the radio puts the center of the narrow CW filter), I get a frequency of 14.399.760 MHz.

A recording of Peanut's signal - tuned to 750 Hz - is [here].  The first half of the recording is in normal CW mode, and the second half is with the narrow filter switched in.  Not bad for 100 mW!

74

HF Beacons / Re: High Frequency Beacon Society master list for beacons

« on: January 05, 2010, 1923 UTC »

Often in forums, there are certain topics that are useful to always have at the top of the listings, so that they don't get "pushed down" the list by more recent topics as they are added.  It is most often seen with things like the rules and posting guidelines, but is also seen with FAQs and other basic information that is useful for people to see when they first visit a forum.  (brief description [here])

Overuse of "sticky" topics can lead to a mess, with a ton of persistent topics that have been deemed "too important" to allow to drop, and the regular rolling topics relegated to a tiny space way down at the bottom of the screen.  Good and moderate use of the "sticky" designator can be very helpful though, as it can keep people from having to ask the same things over and over again, as the relevant topics get pushed out.

In this case, a "sticky" with the master list and/or some basic information might not be a bad idea, since it would always be there at the top whenever someone clicked into the "HF Beacons" forum.  I'm not entirely sure just what would be involved in designating a topic as "sticky", since I've never been in a forum moderator position, but I assume that it's just an option somewhere in the thread controls that the forum moderator can select to turn "stickiness" on and off.

75

HF Beacons / Re: High Frequency Beacon Society master list for beacons

« on: January 05, 2010, 1536 UTC »

Maybe the master list could be given a dedicated "sticky" thread at the top of the forum?